1) Field of the Invention
The present invention relates to a door apparatus.
2) Description of the Related Art
Some vehicles like vans (“one-box” cars) have sliding doors on a side of their bodies, the side parallel to a direction in which the vehicles travel. Such a sliding door usually has a window hole, which can be shut/opened by a window glass capable of freely moving up/down.
In such a vehicle, a full open latch unit and a full closure latch unit are provided between the vehicle body and the sliding door. The full open latch unit is configured to keep the sliding door at a full-open position relative to the vehicle body and the full closure latch unit is configured to keep the sliding door at a full-closed position relative to the vehicle body. Therefore, when the sliding door is at the full-closed position, for example, the sliding door will not slide inadvertently in an opening direction to which the sliding door is opened even if the vehicle body is inclined. Likewise, when the sliding door is at the full-open position, the sliding door will not slide inadvertently in a closing direction to which the sliding door is closed even if the vehicle body is inclined.
If the sliding door is slid in the opening direction with the window glass forgotten to be closed while a foreign object is inserted in the window hole, the foreign object may be caught between a window frame of the window hole and a pillar of the vehicle body. Consequently, damages to both the foreign object and the vehicle body may be caused.
Therefore, a middle stopper mechanism, which stops the sliding door at a position before the full-open position if an openness of the window hole or a degree to which the window hole is opened is greater than a predetermined threshold, even when the sliding door is slid in the door opening direction, may be provided to avoid the above problems, as disclosed in Japanese Patent Application Laid-Open No. 2001-173296 and Japanese Patent No. 3263805.
The middle stopper mechanism includes a middle striker provided at the vehicle body and a stopper member called a “pole” provided at the sliding door so as to be able to swing. When the openness of the window hole is equal to or less than the threshold, the stopper member is engaged with a hook member so as to be kept at a retracted position against a force applied by a forcing unit such as a spring and to not interfere with sliding of the sliding door.
If the openness of the window hole is greater than the threshold, the stopper member is released from being engaged with the hook member, so that the stopper member projects toward the vehicle body by the force applied by the forcing unit. As a result, when the sliding door is slid in the opening direction, the stopper member projected abuts on the middle striker to hinder the sliding door from sliding further. Therefore, even if the foreign object is stuck out through the window hole, the foreign object will not be caught between the window frame and the vehicle body.
The stopper member, however, is moved so as to project whenever the openness of the window hole exceeds the threshold. For example, the stopper member is moved so as to project even if the sliding door is already in the full-open position, and the foreign object cannot be put in/out through the window hole or the foreign object can be put in/out through the window hole but will not be caught between the window frame and the vehicle body.
There is no problem in the stopper member moving so as to be projected when the openness of the window hole exceeds the threshold for preventing the foreign object passing through the window hole from being caught. However, when the sliding door at the full-open position is slid in the closing direction, there is a problem in that a portion of the stopper member which is not originally designed as a portion to be abutted on the middle striker is abutted on the middle striker. Consequently, unpleasant noises are generated during the operation and sliding of the sliding door in the closing direction may be interfered. In particular, when the vehicle body is inclined, the sliding door may slide abruptly in the closing direction, making the above problem more significant.
Furthermore, when operating the sliding door, a user of the vehicle may not always stop the sliding door at the full-open position or the full-closed position. Particularly if the vehicle is long like the vans, a distance for which the sliding door is slided from the full-closed position to the full-open position is long. Therefore, the sliding door may be slided only by a small distance and stopped there (hereinafter referred to as being in a “half-open” state) for putting in/out a small baggage, for example.
When the sliding door is in the half-open state, the full open latch unit and the full closure latch unit of the vehicle do not function. Therefore, if the vehicle is inclined,.the sliding door may possibly start moving due to the gravity.
When the sliding door is closed, a weather strip provided between the sliding door and the vehicle body along the entire circumference sufficiently functions as a pad so as to prevent generation of a loud noise even if the sliding door moves and reaches at a high speed the full-closed position.
However, when the sliding door is operated to open, the sliding door reaches the full-open position with a member called a full-open stopper colliding with a surface of the vehicle body and without the weather strip functioning as the pad. Accordingly, even if the pad such as rubber is provided between the full-open stopper and the surface of the vehicle body, it is difficult to prevent generation of a loud noise if the sliding door moving at a large speed reaches the full-open position. In a vehicle provided with a middle stopper mechanism, it is difficult to ensure sufficient strength with the stopper member. Not only the noise but also a damage to the middle stopper mechanism may thus be caused.
Further, since the stopper member is often provided at a lower portion of the sliding door, mud or water droplets may adhere on the forcing unit. Accordingly, the force applied by the forcing unit is likely to decrease by the adhesion of mud, or by freezing of the water droplets adhered. As a result, the stopper member cannot be fully projected toward the vehicle body, so that when the sliding door with the window hole open is slid in the opening direction, the sliding door may reach the full-open position because the stopper member cannot abut on the middle striker.
Moreover, even if the sliding door is restricted from reaching the full-open position, the sliding door is still able to slide in the opening direction, and getting in/out of passengers is still allowed. Therefore, if the user forgets to close the window glass, closes the sliding door, and leaves the vehicle, things left inside the vehicle may be stolen.